1. Field of the Invention
The present invention relates to an apparatus for adjustment of the longitudinal position of a safety binding on a ski.
2. Description of Pertinent Information
Ski boots are generally maintained on a ski between a front abutment, immobilizing the front end of the boot, and a rear abutment maintaining the heel of the boot on the ski. These front and rear abutments comprise the elements of a safety ski binding. To adapt the safety binding for use with boots of different sizes, bindings have been developed in which the longitudinal position of either the front or rear abutment (generally the rear abutment) is adjustable so that the distance between the front abutment and the rear abutment is adjusted to the longitudinal dimension of the boot to be maintained on the ski.
These apparatus for adjusting the longitudinal position of a safety binding generally comprise a guide fixed to the ski and a base plate attached to the binding. The base plate is adapted to slide in the longitudinal direction in the guide. In addition, the base plate can be locked in the guide at an appropriate longitudinal position corresponding to the length of the boot to be maintained on the ski.
One such apparatus is described in German Patent DE No. 25 21 746. In this apparatus the guide on the ski has, along one of its longitudinal edges, a plurality of spaced apart locking notches. In addition, the base plate is slidable in the longitudinal direction in the guide, and the base plate comprises a plurality of laterally extending teeth positioned along a portion of the longitudinal edge of the base plate facing the notches. Moreover, the width of the base plate is less than the internal width of the guide so that the base plate can slide freely in the guide to allow for the adjustment of the longitudinal position of the base plate. Once the base plate has been placed in the desired longitudinal position, the base plate is locked in the guide in this position by engagement of its laterally extending teeth with the locking notches of the guide under the action of a locking element. This locking element is longitudinally engaged between that side of the guide and the base plate opposite from the side of the guide and the base plate comprising the notches and the locking teeth. The locking element is longitudinally engaged between the base plate and the guide by applying a transverse force on the base plate directed towards the locking notches. This force maintains the engagement of the teeth of the base plate in the locking notches of the guide.
This apparatus has the disadvantage of requiring the use of a locking element which is independent of the binding and which must be forceably engaged longitudinally between the base plate and the guide, an operation which is not easy to carry out. Further, this apparatus does not guarantee that the base plate will be locked in the guide at a particular longitudinal position for a long period of time because the shocks and vibrations resulting from skiing cause a certain lateral play to appear, which leads an unlocking of the base plate from the chosen longitudinal position, thereby permitting the base plate to be longitudinally displaced in the guide and breaking the rigid link between the binding and the ski.
French Pat. No. 2,495,279 of Assignee describes another such adjustment apparatus. In this apparatus the locking element is incorporated into the binding and is biased by an elastic washer. Nevertheless this apparatus is not completely satisfactory because the washer has a considerable elasticity in the transverse direction so that one does not obtain firm maintenance of the base plate in the guide.